Stickies.app is great. It is a wonderful place to jot down quick notes and reminders on your Mac. It has a surprising amount of features for such a simple application. Unfortunately, the ability to sync Stickies across multiple Macs is not one of them.
StickiesSync aims to solve that problem simply and elegantly. StickiesSync implements automatic, instantaneous, silent synchronization of your sticky notes across multiple Macs. Run the installation script once on each Mac, and never worry about it again.
StickiesSync uses a shared folder or server volume to sync your Stickies. For example, you can sync using iDisk, DropBox, Box.net, Windows Live Sync (formerly FolderShare), your own private internet-accessible server, or any other kind of server that gives you full read and write access via file sharing in the Finder.
StickiesSync does not require a service like this. Many free options are available, if you do not already use such a service.